Hey,
I'm in Iowa State University's Formula 1 SAE team... Our goal this year is a sub- 380 lb car with a single cylinder thumper (YZF 450). Anyways, the engine is a dry sump and the team is trying to drop weight where ever possible. Is it possible to drop the dry sump tanks size at all? I know that the tank needs to be there to get the air out of the oil after the crank, but hey, never hurts...

Thanks,
Whis

I hope I posted in the right section...

 

It's just Formula SAE, there's no 1 in there.

You can probably run a smaller tank, but you don't want to go too small as it could have negative implications with regards to oil temps, air in the oil that gets pumped into the engine and some other bad things. How big is the tank currently?

 

You're the engineering student, so do some engineering... learn the theory of how it works, set a few goals or requirements, design something to meet those requirements, build a prototype, and come up with some tests that you can perform to quantify how your new design compares to the old design. Repeat if necessary.

-s-

 

agreed....^ but what are the requirements??

 

lighten you frame. I am a university student as well, (but up north) and the biggest weight savings can be gained by removing all the stupid things that are not needed, and by shaving weight off the chasis and suspension. That will save several pounds while making the oil tank smaller will shave a fraction of a pound, and will most likly cause some problems.

Consider an all aluminum monocoque body, rather then the typical alloy tube body wraped in Fiber glass, or Cabon fiber. This will be lighter, stronger and cheaper then the other types of chasis designs. If you don't belive me do the math on it.

 

The requirements are whatever he needs the system to do. Notice the first step I listed: learn how the system works. I bet you could find some info on howstuffworks.com or google.com


It probably needs to supply oil to the pressure pump, which is pumping at a certain rate. It probably needs some baffling so that the pump doesn't run dry when the car is cornering hard (many FSAE cars are cornering in excess of 1.3g) or braking hard. It probably needs to fit in the car, and since this is a racecar you might want to mount it low to keep your CG height close to the ground.

These are just a few things to consider, I'm sure there are other things that you require of a dry sump tank.


Regarding weight, don't forget that the tank is going to be mounted in the car (so the chassis has to be large enough to fit it on there somewhere) and will be filled with fluid. Decreasing the size of the tank might not do much, but if you can safely use a quart less oil or decrease the size of your chassis then that might be worth the effort.

 

If you are building a 450 single car and you want it to be light then I would suggest you check out Cal Poly San Luis Obispo. Our car weighed in at 319 lbs at Fontana 2 years ago. Unlike RMIT's IRS we used a straight axle rear end machined from a single piece of 2024. To eliminate the need for a differential the inside rear tire lifts off of the ground anywhere north of ~.8g's. This action is assisted by a high kingpin angle built into the uprights of the front suspension. The car was light and extremely fast, much faster than all of our previous cars which used R6 motors and front and rear independent suspension and weighed ~435 lbs.

Reguarding chassis construction: we used carbon fiber with Nomex core for the tub and 4130 tubing for the rear subframe but I will have to agree with no_name. Using an aluminum sheet monocoque will be much cheaper and easier to build (I think at least, I've never done it but composite is very difficult and time consuming). You will also get more points in cost if you build an aluminum monocoque. Also judges who know their *** from a hole in the ground will love it. Keep in mind that the stiffness-to-weight ratio of a carbon tub will be much higher than that of an aluminum monocoque so the monocoque will be heavier, but once you know how to build a monocoque you will be able to put them together quickly and efficiently (VERY IMPORTANT for next year and absolutly not applicable to composites).

Good luck!